Service Provider Evolution

In this era of e-commerce and e-businesses, many companies rely on distributed network services as a significant part of their entire business model. As a result, Internet-related initiatives require recruiting, staffing and funding to operate. Typically, these expenses represent a significant cost and not one that decreases with time. Service providers address these concerns by creating economies of scale. By serving numerous clients, they reduce costs for everyone. In fact, if they manage bandwidth and service usage properly, service providers can provide better customer service than internal providers.

However, service providers need to manage the following issues:

• Bandwidth hogging that decreases access to network resources

• Maximizing potential business applications

• Ensuring high performance across applications

• Customizing bandwidth to expand services

In order to manage these issues, service providers must have an accurate map of their network. They must monitor traffic to determine normal and abnormal usage and establish baseline metrics to be able to efficiently monitor productivity.

Factors to consider

• Burst traffic: Burst traffic is abnormal usage that typically lasts only for a short time during peak periods, for example, when a popular, downloadable file goes online. Typically, burstable traffic consists of lower priority requests that may receive decreased bandwidth.

• Interactive traffic: Interactive traffic typically refers to normal use of a web site, such as users following links. If it is high-priority traffic, it must be fast. Other application-level clients require a minimal amount of bandwidth to provide mission-critical services.

• Non-mission critical traffic: Employees behind a router may be using network resources for personal reasons. Such traffic may usually be assigned lower bandwidth and priority.

• Mission-critical traffic: With mission-critical traffic, incoming orders for example, must be given a high priority, if not the highest priority, and a substantial amount of available bandwidth.

• SLAs: In some cases, service providers may have Service Level Agreements (SLAs) in place with clients, and are contractually bound to provide a set amount of dedicated bandwidth and server resources. Service providers must monitor this traffic to meet contractual obligations.

Bandwidth Management

This process includes classifying traffic, managing bandwidth allocation and mapping traffic classes.

Classifying traffic

There are a number of ways to classify traffic–server names, network subnets, destination IP and port, source IP and port, requested file type–the list goes on. However, propagating a client request to a fulfillment server should be automatic and transparent to the requestor. Classifying traffic enables network managers to better track requests and allocate resources based on priorities. Is an FTP request from accounting more important than an HTTP request from human resources? This functionality also enables service providers to establish priorities based on application usage and the nature of request as well as any other metric they want to use.

Managing bandwidth allocation

Once traffic is classified, specific configurations can be defined to control how bandwidth is distributed. The two most widely used methods are partitions and policies.

• Partitions: Partitioning creates a separate, exclusive channel for traffic that manages the total network usage by traffic type, for example, FTP traffic might be assigned 10 percent of network resources, e-mail might receive 10 percent and incoming HTTP requests might receive 50 percent. Unused bandwidth in that traffic type can be placed in a pool that is available to other applications to speed up the overall network.

• Policies: Rate-based policies set a minimum amount of guaranteed bandwidth for burst traffic. Priority policies set aside bandwidth for traffic that must compete with burst traffic. These policies provide network stability and efficient fulfillment of all requests and responses.